Lfric fem base_mesh dependencies

[Juan Manuel Castillo Sanchez (ukmo-juan-castillo)]

PR Summary

Sci/Tech Reviewer:
Code Reviewer: mo-lucy-gordon

There are changes in the init_fem and the assign_coordinate_field subroutines to read the geometry and topology of meshes from the mesh object rather than from the base_mesh namelist. There is also a change fixing a but in the is_topology_non_periodic subroutine of the mesh object.

• linked Mesh topology bug lfric_apps#529

• closes init_fem dependencies on base_mesh #366

• fixes init_fem dependencies on base_mesh #366

Code Quality Checklist

• I have performed a self-review of my own code
• My code follows the project's style guidelines
• Comments have been included that aid understanding and enhance the readability of the code
• My changes generate no new warnings
• All automated checks in the CI pipeline have completed successfully

Testing

• I have tested this change locally, using the LFRic Core rose-stem suite
• If required (e.g. API changes) I have also run the LFRic Apps test suite using this branch
• If any tests fail (rose-stem or CI) the reason is understood and acceptable (e.g. kgo changes)
• I have added tests to cover new functionality as appropriate (e.g. system tests, unit tests, etc.)
• Any new tests have been assigned an appropriate amount of compute resource and have been allocated to an appropriate testing group (i.e. the developer tests are for jobs which use a small amount of compute resource and complete in a matter of minutes)

Both the lfric_core and lfric_apps tests have been run, see results below.

trac.log (lfric_core)

Test Suite Results - lfric_core - lfric_fem_dependencies/run1

Suite Information

Item	Value
Suite Name	lfric_fem_dependencies/run1
Suite User	juan.m.castillo
Workflow Start	2026-05-30T15:23:56
Groups Run	all

Dependency	Reference	Main Like
lfric_core	ukmo-juan-castillo/lfric_core@lfric_fem_dependencies	False
SimSys_Scripts	MetOffice/SimSys_Scripts@cab3315	True

Task Information

✅ succeeded tasks - 402

trac.log (lfric_apps)

Security Considerations

• I have reviewed my changes for potential security issues
• Sensitive data is properly handled (if applicable)
• Authentication and authorisation are properly implemented (if applicable)

Performance Impact

• Performance of the code has been considered and, if applicable, suitable performance measurements have been conducted

AI Assistance and Attribution

• Some of the content of this change has been produced with the assistance of Generative AI tool name (e.g., Met Office Github Copilot Enterprise, Github Copilot Personal, ChatGPT GPT-4, etc) and I have followed the Simulation Systems AI policy (including attribution labels)

Documentation

• Where appropriate I have updated documentation related to this change and confirmed that it builds correctly

PSyclone Approval

• If you have edited any PSyclone-related code (e.g. PSyKAl-lite, Kernel interface, optimisation scripts, LFRic data structure code) then please contact the TCD Team

Sci/Tech Review

• I understand this area of code and the changes being added
• The proposed changes correspond to the pull request description
• Documentation is sufficient (do documentation papers need updating)
• Sufficient testing has been completed

(Please alert the code reviewer via a tag when you have approved the SR)

Code Review

• All dependencies have been resolved
• Related Issues have been properly linked and addressed
• CLA compliance has been confirmed
• Code quality standards have been met
• Tests are adequate and have passed
• Documentation is complete and accurate
• Security considerations have been addressed
• Performance impact is acceptable

[github-actions]

Hello Juan Manuel Castillo Sanchez (@ukmo-juan-castillo)! 👋

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